*          ATLANTIC TC GENESIS INDEX           *
                      *                GFS VERSION                   *
                      *           AL972021 09/19/21 00 UTC           *

TIME (hr)           0     6    12    18    24    36    48    60    72    84    96   108   120
Prob of Genesis                                       52%                                 69%

LAT  (deg N)      9.8  10.6  11.5  12.2  13.0  15.2  18.0  19.1  19.7  20.2  20.7  21.4  20.7
LON  (deg W)     27.4  27.6  28.0  28.8  29.3  31.3  32.6  33.6  33.7  34.0  35.3  36.7  37.9
DTL  (km)        1186  1189  1193  1254  1288  1481  1648  1745  1745  1770  1900  2041  2174
TRACK SOURCE     AP23  AP23  AP23  AP23  AP23  AP23  AP23  AP23  AP23  AP23  AP23  AP23  TABM

TCGI  0-48h Genesis Forecast:   52% is  1.8 times the sample mean (  30%)
TCGI 0-120h Genesis Forecast:   69% is  1.6 times the sample mean (  43%)

---------------------------------------------------------------------------------------------
INDIVIDUAL PREDICTOR CONTRIBUTIONS TO PROBABILITY OF GENESIS 

               *******  48-HR ******   ******* 120-HR ******
                   AVG   TCGI   CONT       AVG   TCGI   CONT
DIVERGENCE        -1.0    0.4   5.1%       1.0    0.2   9.9%
VORTICITY          1.7    1.8   9.6%       1.4    1.4  15.9%
VERTICAL SHEAR    16.3   10.0  19.8%      18.4   12.2  22.6%
RH                73.1   76.7  -0.2%      70.9   66.5   2.8%
GOES              29.1   30.7   1.6%      29.3   30.7   1.1%
DVORAK             0.8    2.0  16.5%       0.8    2.0  16.2%

---------------------------------------------------------------------------------------------
PREDICTOR DEFINITIONS (Averaged Over 500 km Radius)

GENESIS CLIM   = Climatological Prob (%) of Genesis (Source: NHC-TAFB Invest Database) 
DIVERGENCE     = GFS 850 hPa Horizontal Divergence (x10-7 s-1)
VORTICITY      = GFS 850 hPa Vorticity (x10-6 s-1)
VERTICAL SHEAR = GFS 200-850 hPa Vertical Shear (kt)
RH             = GFS 600-850 hPa Relative Humidity (%)
GOES           = GOES Water Vapor Pixels Colder than -40C (%)
DVORAK         = Dvorak T-number, source: TAFB

Version 3.0, July 2018